Sharpening machine



July" 15, 1969 J. J. BURNS I SHARPENING MACHINE INVENTOR J. BURNS 5 Sheets-Sheet 1 Filed June 14, 1967 ATTORNEY July 15, 1969 J. J. BURNS 3,455,187

SHARPENING MACHINE Filed June 1967 s Sheets-Sheet 2 I 0 A22 I l v 62 ll-I l INVENTOR.

JOHN J. BURNS ATTORNEY y 15, 1969 J. J. BURNS 3,455,187

SHARPENING MACHINE Filed June 14, 1967 s sheets-sheet s F I G. 3

INVENTOR. JOHN J. BURNS ATTORNEY July 15, 1969 J. J. BURNS SHARPENING MACHINE 5 Sheets-Sheet 4 Filed June 14, 1967 INVENTOR' BURNS JOHN J.

ATTORNEY July 15, 1969 J. J. BURNS SHARPENING MACHINE Filed June 14, 1967 5 Sheets-Sheet 5 w O Z66 W I\ J\ I\ Fl G. 7

FIG. 8

INVENTOR. FIG. 9 JOHN J. BURNS QL W ATTORNEY 3,455,187 SHARPENING MACHINE John J. Burns, 26 Church Lane, Portsmouth, RI. 02871 Filed June 14, 1967, Ser. No. 645,958

Int. Cl. B2311 63/12 US. CI. 76-40 16 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to improvementsin sharpening machines and more particularly to an improved sharpening machine for toothed tools, such as saws, rotary saws, band saws and others. This invention constitutes an improvement over my prior patent, U.S. Patent No. 3,008,357, issued Nov. 14, 1961, for Saw Sharpening Tool.

An object of the present invention is to provide an improved sharpening machine wherein novel means is employed for controlling the bevel angle of the teeth being sharpened.

Another object of the present invention is to provide an improved sharpening machine wherein the tooth shape can be predetermined.

Still another object of the present invention is to pro vide an improved sharpening machine wherein means is provided for predetermining the shape of the tooth to be sharpened and for varying the movement of the grinding wheel according to the predetermined shape.

A still further object of the present invention is to provide an improved sharpening machine for toothed tools wherein the up" and down movement of the grinding wheel is so controllable that teeth of various heights and skip teeth designs can be accommodated.

A further object of the present invention is to provide an improved sharpening machine for toothed tools wherein the feed of the work piece being sharpened is easily adjustable from a zero tooth pitch to an extremely long itch. p Still another object of the present invention is to provide an improved sharpening machine for toothed tools wherein the oscillation of the grinding wheel to effect sharpening at bevel angles is accomplished in a simplified and more effective fashion than heretofore.

Another object of the present invention is to provide an improved centering means for properly locating the teeth to be sharpened in relation to the grinding wheel.

Various other objects and advantages will become apparent from the detailed description to follow.

The invention comprises a housing having a main shaft which is vertically reciprocable anda driven shaft which is continuously rotated in use. The main shaft carries a grinding wheel which moves up and down over the teeth to sharpen the same. Cam means function off the driven shaft to periodically lift the main shaft. Further cam means oscillate a lever which is coupled to the main shaft to oscillate it and thus the grinding wheel for performing bevel grinding of the teeth. The feed of the teeth is effected by cam means driven by the driven shaft which cam means pivots the feed lever and feed pawls carried thereby. The extent of feed and angle of bevel are adjustable.

3,455,187 Patented July 15, 1969 ice Also tooth height and toothless sections are accommodated.

In the drawings:

FIGURE 1 is a perspective view of my improved machine as viewed from the front;

FIGURE 2 is a perspective view of my improved sharpening machine as viewed from the left rear;

FIGURE 3 is another perspective view showing more of the right side of the machine.

FIGURE 4 is a perspective view of the interior of the machine showing operating means;

FIGURE 5 is a perspective view showing the feed means of the machine;

FIGURE 6 is a detail sectional view taken substantially on the plane of line 66 in FIGURE 4.

FIGURES 7, 8 and 9 show various profiling shoes and possible respective tooth configurations.

Referring more particularly to the drawings wherein like numerals apply to like parts throughout it will be seen that I have provided an improved sharpening machine 10 which includes a housing 12, tool support means 14, drive means 16, grinding means, 18, blower means 20, grinding wheel reciprocating means 22, grinding wheel oscillating means 24, tool feed means 26, operating means 28 for the means 22, operating means 30 for the means 24 and operating means 32 for the means 26.

The housing 12 is of 'cast construction and includes a base 34. front wall 36, rear wall 38, top wall 40, and one side wall 42. i

The tool support means of the present machine does not constitute part of the present invention and has features similar to the support means shown and described in my said prior patent and a more detailed description is deemed unnecessary. Suffice it to say the workpiece such as the saw S of FIGURE 1 is clamped on the carrier by the clamps 46 and wing nuts 48.

The carrier is longitudinally movable with the table rail 50 which is slidably carried on swing plate 44. An index bar 52 is provided for use, if desired. A finger clamp 54 and locking lever 56 are provided for gripping the upper edge of the saw in position, as will be understood. FIGURE 2 shows a centering means which includes a thumb wheel screw 58 through the threaded lobe 60 on back of the swing plate 44. Adjustment of screw 58 will position and line up the clamping jaws and 62 so as to hold the saw in the correct centered relation to the grinding wheel.

The drive means 16 includes a motor 64 mounted on bracket 66 which is secured to the housing sothat the motor drive shaft 68 is perpendicular to housing side wall 42. The shaft 68 has a worm 70 cradled in the shell 72 formed integral with the housing side wall. The drive means further includes a driven shaft 74 journaled at one end in boss 76 on rear wall 38 and at its other end projecting through bearing boss 78 integral with side wall 42. A gear 80 is enmeshed with worm 70 so as to be driven thereby. Shaft 74 has a bevel drive gear 82 retatable therewith for a purpose to be described. Also, shaft 74 has an eccentric lift cam 84 and an eccentric feed cam 86 mounted for rotation thereby, for purposes to be described.

The motor 64 has a pulley 88 over which the flexible and resilient belt 90 is passed. The latter passes over pulley 92 rotatably supported on shaft 94 and over pulley 96 mounted on shaft 98. The belt passes over pulley 100 connected to shaft 102 which is the grinding wheel shaft.

The grinding means 18 includes the grinding wheel 104 driven by its shaft 102. and partially within shield 106 which supports shaft 108. Shield 106 is secured to the lower end of the main shaft 108 by sleeve 110, and is movable therewith and thereby.

The blower means 20 is somewhat similar to my prior patent construction and includes a blower 112 with a hood at 114 for collection of the flying particles. The blower means forms no part of the present invention.

The grinding wheel reciprocating means 22 includes an elongate lift arm 116 lying on a generally horizontal plane parallel to and over the axis of shaft 74. Arm 116 has one end pivoted on pivot 110 between the car 120 and side roller 128 rotatably carried thereon for following engagement with the tooth profiling shoe 230 which will be more fully described hereinafter. The bolt 122 is engaged through the weighted piston block 132 for movement thereof upon lifting of arm 116. The piston 132 has a slide bore therethrough for the main shaft 108. Guide pins are provided at 134. Thus the shaft 108 is lifted by arm 116 and returned by gravity.

The grinding wheel oscillating means 24 will now be described. The means 24 includes an elongate oscillating lever 136 pivoted on pin 138 through bracket 140 secured to side wall 42. One end of lever 136 has a link 142 pivoted on pin 144 with a cam follower roller 146 rotatably carried on the free end of link. 142. The roller 146 is shown in a position out of engagement with oscillating earn 148 whereby no oscillation of shaft 108 occurs, as when the teeth to be sharpened are not beveled.

By pivoting link 142 and pinning it to lever 136 by pin 150 through hole 152, the roller 146 is held against the peripheral cam surface 154 as shown in dotted lines in FIGURE 4.

The oscillating cam 148 is of circular shape having a cylindrical peripheral wall formed with high and low points as at 156, 158. A bevel gear 160 is connected to earn 148 and is rotatably driven by bevel gear 82 on driven shaft 74.

The opposing end of lever 136 has a fork 162 in which one leg 164 of L-shaped arm 166 is engaged for pivoting thereby. The arm 168 is graduated for indicating various bevel degrees and is adjustablyreceived through the shaft 108. Thus shaft 108 will oscillate back and forth through a preselected angle while travelling up and down.

The tool feed means is best shown in FIGURES 4 and as including a feed leve'r 170 pivoted on pin 172 to side wall 42, see FIGURE 2. The lower end of lever 170 has pawls 174 adjustably secured thereto by the knuckle 176 rotatably received in the socket 178. Adjusting screw 180 controls the pawl angle. The pawls further are carried on bracket 182 which is pivoted on pin 184 for limited freedom in riding over the teeth during retracting movement of lever 170.

The upper end of lever 170 has a long screw 186 rotatably carried thereby with an adjusting block 188 en- I gaged on said screw for longitudinal movement upon rotation of screw 186. Block 188 has a cam follower roller 189 carried thereby for responsive engagement with the feed cam 190 which is pivoted on pin 192 through hole 193 to side wall 42. Cam lever 190 has a roller 194 in following engagement with feed cam eccentric 196 fixed to driven shaft 74. Graduations are provided on lever surface 170 (see arrows) to correspond to zero tooth pitch up to a maximum tooth pitch of preselected size. Of course, the pawls in moving in one direction slide the tool and its carrier one tooth forward for sharpening thereof by grinding wheel and the pawls on retraction pivot and ride over the teeth in readiness for the next feed movement.

The operating means 28 for the lift arm 116 is best shown in FIGURES 4 and 6. A yoke 200 is pivoted on one leg by bolt 204 to boss 78 and has an upper leg 206 disposed beneath lift arm 116. A lift cam follower 208 rides on in following engagement with lift cam 84 to effect pivoting of yoke 200.

A tooth profile determining shoe 230 is removably carried on yoke arm 206 by lug 212 engaged in slot 210. One end of shoe 13tl is engaged by thumb screw 214 (see FIG- URE 2) whereby the angle of the shoe can be varied. Thus in an up" position shoe 230 increases the back side of a tooth and in a down position lowers or flattens the back side of the tooth. Shoe 230 effects the lifting movement of lift arm 116 by its engagement with the follower cam roller 128. The shoe 230 can be interchanged to control or conform to the shape of the teeth being sharpened.

An important feature connected with the lift arm comprises the skip" tooth control. The wheel 216 rides on and through top Wall 40 and is threaded through lift arm 116. By adjustiment of screw 216 the down movement in following the lift cam shoe 130 is limited whereby a skip tooth configuration can be achieved.

I prefer to provide a set of three profile shoes as shown at 230 in FIGURE 7, 240 in FIGURE 8 and 250 in FIG- URE 9. Each shoe can accommodate a particular tooth shape as shown in the respective figures, although further variations are obviously possible.

Obviously, straight saws, circular saws and band saws can be handled and differ only in their mounting.

The operation of the machine is believed to be obvious in view of the foregoing detailed description. It will be understood that electrical controls form no part of the present invention. A switch is provided for energizing the motors as at 220. The driven shaft 74 operates the means 30 to effect oscillation of the grinding wheel, the means 28 to effect lifting of the grinding wheel and the means 32 to effect feeding of the work. The grinding wheel is driven by extensible belt which stretches during up and down and oscillating movement of the grinding wheel.

The shape of the teeth can be varied and controlled to an almost infinite degree.

In view of the foregoing it is believed that I have provided an improved sharpening machine which fulfills the objects hereinbefore enumerated.

As this invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within the metes and bounds of the claims or that form their functional as well as conjointly cooperative equivalents, are therefore intended to be embraced by these claims.

I claim:

1. A sharpening machine for toothed cutting tools comprising a housing, a grinding wheel, a shaft slidably and rotatably carried in said housing and rotatably supporting said grinding wheel, means effecting reciprocation of said shaft, means effecting oscillation of said shaft, means for supporting a toothed tool in preselected relation to the grinding wheel, means effecting tooth-by-tooth feed of the tool to be sharpened transversely of the machine and in relation to the grinding wheel, means variable to control movement of the grinding wheel in relation to the tooth being sharpened to control the profile of that tooth.

2. A sharpening machine for toothed cutting tools according to claim 1 wherein said variable means includes a link operably coupled to said shaft to effect pivoting thereof, said link being adjustable as to length between its fulcrum and said shaft to vary the angle of oscillation.

3. A sharpening machine according to claim 1 wherein said means for effecting oscillation of said shaft includes an oscillating lever swivelly mounted in said housing on an axis parallel to said shaft, one end of said lever having a cam follower, a cam mounted for rotation on an axis at right angles to said lever axis and spaced therefrom, said cam having a peripheral cam surface formed with predetermined high and low points adapted to cooperate with said lever cam follower to effect swivclling of the lever, means operably connecting said lever to said shaft to effect oscillation.

4. A sharpening machine according to claim 3 wherein said last recited means includes a link, said variable means including said link and means adjusting the length of said link between its fulcrum and said shaft to vary the angle of oscillation.

5. A sharpening machine according to claim 4 wherein said link is an angulated rod having one arm adjustably engaged through said shaft and another arm engaged by said oscillating lever.

6. A sharpening machine according to claim 1 wherein said means for effecting oscillation of said shaft includes an oscillating lever swivelly mounted in said housing on an axis parallel to said shaft, one end of said lever having a cam follower, a cam mounted for rotation on an axis at right angles to said lever axis and spaced therefrom, said cam having a peripheral cam surface formed with predetermined high and low points adapted to gooperate with said lever cam follower to effect swivelling of the lever, means operably connecting said lever to said shaft to effect oscillation, and said cam follower being carried by an arm, said arm being adjustable so as to be held in one of two positions, in one of which positions said cam follower is held against said cam and in the other of which positions said cam follower is held out of engagement with said cam.

7. A sharpening machine according to claim 1 wherein said means effecting reciprocation of said shaft includes a driven shaft rotatably carried in said housing on an axis perpendicular to said first mentioned shaft, a lift arm pivotally supported in said housing and generally parallel to said driven shaft, an eccentric lift cam on said first mentioned shaft, a lift cam follower carrier pivotally mounted in said housing on an axis parallel to the axis of said driven shaft and having a cam follower rotatably carried thereby and engageable with said eccentric lift cam whereby upon rotation of said driven shaft said cam follower is shifted and said cam follower carrier pivoted on its axis, means operatively coupling said cam follower carrier with said lift arm to cause pivoting thereof, and means coupling said lift arm with said first mentioned shaft to effect periodic lifting thereof.

8. A sharpening machine according to claim 7 wherein said means operatively coupling said cam follower carrier with said lift arm includes a tooth profile shoe adjustably carried by said carrier and a follower roller on said lift arm engaged by said profile shoe.

9. A sharpening machine according to claim 8 wherein said tooth profile shoe is interchangeable according to the desired tooth shape.

10. A sharpening machine according to claim 9 wherein said profile shoe is pivotally adjustably mounted on said carrier.

11. A sharpening machine according to chaim 1 wherein said means effecting reciprocation of said shaft includes a lift arm pivotally mounted in said housing and operably coupled with said shaft whereby pivoting of said lift arm in one direction lifts said shaft and in an opposite direction drops said shaft, and means adjustably limiting the movement of said lift arm in said opposite direction whereby skip teeth sharpening can be effected.

12. A sharpening machine according to claim 1 wherein said supporting means for the tool to be sharpened includes a swing plate, a table rail slidably carrying said swing plate for relative longitudinal movement, and means for centering the tool to be sharpened so that the teeth thereof are centered with relation to the grinding wheel.

13. A sharpening machine according to claim 12 wherein said means includes clamping jaws for the tool and screw means cooperatively associated with said clamping jaws.

14'. A sharpening machine according to claim 1 wherein said means for effecting tooth-by-tooth feed of the tool includes a feed lever pivotally carried by said housing, a feed pawl means engageable to progress the tool during sharpening and operably coupled with said feed lever for reciprocation thereby, a rotatable eccentric feed cam rotated in predetermined relation to said shaft movement, a feed cam follower mounted so as to be pivoted by said feed cam, and means operably coupling said feed lever with said feed cam follower for effecting pivoting of the latter.

15. A sharpening machine according to claim 14 wherein said last recited means includes a contact member longitudinally adjustably carried by said feed lever and engageable with said feed cam follower at a point preselectedly spaced from the fulcrum thereof to determine the extent of feed of said feed pawl means.

16. A sharpening machine according to claim 1 Wherein said means effecting reciprocation of said shaft includes a driven shaft rotatably carried in said housing on an axis perpendicular to said first mentioned shaft, a lift arm pivotally supported in said housing and generally parallel to said driven shaft, an eccentric lift cam on said first mentioned shaft, a lift cam follower carrier pivotally mounted in said housing in an axis parallel to the axis of said driven shaft and having a cam follower rotatably carried thereby and engageable with said eccentric lift cam whereby upon rotation of said driven shaft said cam follower is shifted and said cam follower carrier pivoted on its axis, means operatively coupling said cam follower carrier with said lift arm to cause pivoting thereof, and means coupling said lift arm with said first mentioned shaft to effect periodic lifting thereof, and wherein said means effecting oscillation of said first mentioned shaft includes an oscillating lever swivelly mounted in said housing on axis parallel to said shaft, one end of said oscillating lever having a cam follower, a cam mounted for rotation on an axis at right angles to said lever axis and spaced therefrom and said cam having a cylindrical cam surface formed with predetermined high and low points adapted to cooperate with said lever cam follower to effect swivelling of the oscillating lever, and means operably connecting said oscillating lever to said shaft to effect oscillation and disengageable therefrom to free said shaft from oscillation.

References Cited UNITED STATES PATENTS BERNARD STICKNEY, Primary Examiner US. Cl. X.R. 5133 

